cmdline: support backspace key

Support windows putty "\b"(Ctrl-H) backspace key.

Signed-off-by: Xueming Li <xuemingl@mellanox.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>

lib/librte_cmdline/cmdline_rdline.c

@@ -331,6 +331,7 @@ rdline_char_in(struct rdline *rdl, char c)
 
 		/* delete 1 char from the left */
 		case CMDLINE_KEY_BKSPACE:
+		case CMDLINE_KEY_BKSPACE2:
 			if(!cirbuf_del_tail_safe(&rdl->left)) {
 				rdline_puts(rdl, vt100_bs);
 				display_right_buffer(rdl, 1);

lib/librte_cmdline/cmdline_vt100.c

@@ -95,6 +95,7 @@ const char *cmdline_vt100_commands[] = {
 	"\020",
 	"\016",
 	"\033\144",
+	vt100_bs,
 };
 
 void

lib/librte_cmdline/cmdline_vt100.h

@@ -117,6 +117,7 @@ extern "C" {
 #define CMDLINE_KEY_CTRL_P 23
 #define CMDLINE_KEY_CTRL_N 24
 #define CMDLINE_KEY_META_D 25
+#define CMDLINE_KEY_BKSPACE2 26
 
 extern const char *cmdline_vt100_commands[];